Asthma

From an epidemiological point of view four issues are briefly emphasized here: the definition of asthma, time trends and regional differences, and risk factors for asthma. Furthermore, I will focus upon a few aspects regarding the relation between exercise and asthma. The definition of asthma has presented problems for those involved in studying the disease in general populations, where the estimates rely solely on reported asthma and respiratory symptoms. A standardized questionnaire does not fully overcome differences in languages and interpretations of the concepts of asthma and wheeze over time and in different communities. Although the belief of an upward trend of childhood asthma seems to be widely accepted, studies with the proper methodology to investigate this issue are scarce. The prevalence of asthma varies within and between countries. There is no clear urban rural gradient, and the prevalence of atopy appears to be higher in western than in eastern Europe. Amazingly little is still known about genetic and environmental factors that are causally related to the manifestation of allergic disorders in previously asymptomatic individuals. The effect of exercise on asthma may be many-sided. Children with asthma can actively take part in sport. However, to what extent extensive exercise may affect the occurrence of bronchial responsiveness is unclear, and among athletes exercise may be a risk factor for the development of “athlete's asthma”. In conclusion, epidemiological studies have to date not reached their potential due to the lack of longitudinal studies including objective measures of exposures and health outcomes. Causal inference is limited, and further studies designed to answer specific research questions are needed.

Asthma, epidemiology, exercise, sports.

References

• 1 Ciba Guest Symposium . Terminology, definitions and classifications of chronic pulmonary emphysema and related conditions.  Thorax. 1959;  14 286-299
• 2 Respiratory Health Effects of Passive Smoking .Lung Cancer and Other Disorders. Washington, DC; U.S. Environmental Protection Agency: EPA/600/6 - 90/006F 1992
• 3 Aas K. Heterogeneity of bronchial asthma. Sub-populations - or different stages of the disease.  Allergy. 1981;  36 3-14
• 4 American Thoracic Society . Definitions and classifications of chronic bronchitis, asthma and pulmonary emphysema.  Am Rev Respir Dis. 1962;  85 762-768
• 5 Anderson H R, Butland B K, Strachan D P. Trends in prevalence and severity of childhood asthma.  BMJ. 1994;  308 1600-1604
• 6 Anderson H R. Is asthma really increasing.  Paed Resp Med. 1993;  1 6-10
• 7 Asher M I, Keil U, Anderson H R, Beasley R, Crane J, Martinez F D, Mitchell E A, Pearce N, Sibbald B, Stewart A W, Strachan D, Weiland S K, Williams H C. International study of asthma and allergies in childhood (ISAAC): rationale and methods.  Eur Respir J. 1995;  8 483-491
• 8 Austin J B, Russel G, Adam M G, Makintosch D, Kelsey S, Peck D F. Prevalence of asthma and wheeze in the Highlands of Scotland.  Arch Dis Child. 1994;  71 211-216
• 9 Barry D, Burr M L, Limb E S. Prevalence of asthma among 12 year old children in New Zealand and South Wales: a comparative surrey.  Thorax. 1991;  46 405-409
• 10 Bjørksten B. Risk factors in early childhood for the development of atopic diseases.  Allergy. 1994;  49 400-407
• 11 Bjørksten B. Environmental factors and respiratory hypersensitivity: Experiences from studies in Eastern and Western Europe.  Toxicology Letters. 1996;  86 93-98
• 12 Bjørksten B. The intrauterine and postnatal environments.  J Allergy Clin Immunol. 1999;  104 1119-1127
• 13 Brunekreef B, Dockery D, Krzyanowski M. Epidemiologic studies on short term-effects of low levels of major ambient air pollution components.  Environ Health Perspect. 1995;  103 3-13
• 14 Bråbæck L, Breborowicz A, Dreborg S, Knutsson A, Pieklik H, Bjørksten B. Atopic sensitization and respiratory symptoms among Polish and Swedish school children.  Clin Exp Allergy. 1994;  24 826-835
• 15 Burney P GJ, Chinn S, Rona R J. Has the prevalence of asthma increased in children? Evidence from the national study of health and growth 1973 - 86.  BMJ. 1990;  300 1306-1310
• 16 Burr M L, Butland B K, King S, Vaughan-Williams E. Changes in asthma prevalence: two surveys 15 years apart.  Arch Dis Child. 1989;  64 1452-1456
• 17 Carlsen K H, Oseid S, Odden H, Mellbye E. The response to heavy swimming exercise in children with and without bronchial asthma. In: Oseid S, Carlsen KH (eds) Children and Exercise XIII. Champaign, Illinois; Human Kinetics Publishers 1989: 351-360
• 18 Clark C J. Asthma and exercise: a suitable case for rehabilitation?.  Thorax. 1992;  47 765-767
• 19 Cookson W OCM, Moffatt M F. Asthma: An epidemic in the absence of infection?.  Science. 1997;  275 41-42
• 20 Dodge R R, Burrows B. The prevalence and incidence of asthma-like symptoms in a general population sample.  Am Rev Respir. Dis 1980;  122 557-575
• 21 Duffy D, Martin N, Battistutta D, Hopper J. Genetics of asthma and hay fever in Australian twins.  Am Rev Respir Dis. 1990;  142 1351-1358
• 22 Fitch K D. Management of allergic Olympic athletes.  J Allergy Clin Immunol. 1984;  73 722-727
• 23 Freed A N. Models and mechanisms of exercise-induced asthma.  Eur Respir. J 1995;  8 1770-1785
• 24 Hanrahan J, Tager I, Castile R, Segal M, Weiss S, Speizer F. Pulmonary function measures in healthy infants.  Am Rev Respir Dis. 1990;  140 1127-1135
• 25 Harris J R, Nystad W, Magnus P. Using genes and environment to define asthma and related phenotypes: applications to multivariate data.  Clin Exp Allergy. 1998;  28 43-45
• 26 Harris J R, Magnus P, Samuelsen S O, Tambs K. No evidence for effects of family environment on asthma.  Am J Respir Crit Care Med. 1997;  156 43-49
• 27 Heir T. Longitudinal variation in bronchial responsiveness in cross-country skiers and control subjects.  Scand J Med Sci Sports. 1994;  4 134-139
• 28 Heir T, Oseid S. Self-reported asthma and exercise-induced asthma symptoms in high-level competitive cross-country skiers.  Scand J Med Sci Sports. 1994;  4 128-133
• 29 Hill R, Williams J, Tattersfield A, Britton J. Changes in use of asthma as a diagnostic label for wheezing illness in schoolchildren.  Br Med J. 1989;  299 898
• 30 Holt P G, Sly P D. Allergic respiratory disease: strategic targets for primary prevention during childhood.  Thorax. 1997;  52 1-4
• 31 Larsson K, Ohlsen P, Larsson L, Malmberg P, Rydstøm P O, Ulriksen H. High prevalence of asthma in cross country skiers.  BMJ. 1993;  307 1326-1329
• 32 Larsson L, Hemmingson P, Boethius G. Self-reported obstructive airway symptoms are common in young cross-country skiers.  Scand J Med Sci Sports. 1994;  4 124-127
• 33 Lenney W, Wells N-E J, O'Neill B A. The budren of paediatric asthma.  Eur Respir rev. 1994;  4 49-62
• 34 Magnus P, Jaakkola J K. Secular trend in the occurrence of asthma among children and young adults: critical appraisal of repeated cross sectional surveys.  BMJ. 1997;  314 1795-1799
• 35 Makker H K, Holgate S T. Mechanisms of exercise-induced asthma.  Eur J Clin Invest. 1994;  24 571-585
• 36 Mc Fadden E Jr, Gilbert I A. Execise-induced asthma.  N Engl J Med. 1994;  330 1362-1367
• 37 Mitchell E A, Asher A. Prevalence, severity and medical management of asthma in European school children in 1985 and 1991.  J Paediatr Child Health. 1994;  30 398-402
• 38 Muns G. Effect of long-distance running on polymorphonuclear neutrophil phagocytic function of the upper airways.  Int J Sports Med. 1993;  15 96-99
• 39 Nafstad P, Øie L, Mehl R, Gaarder P I, Lødrup-Carlsen K C, Botten G, Magnus P, Jaakkola J K. Residential dampness problems and symptoms and signs of bronchial obstruction in young Norwegian children.  Am J Respir Crit Care Med. 1998;  157 410-414
• 40 Nieman D. Exercise, upper respiratory tract infection, and the immune system.  Med Sci Sports Exerc. 1994;  26 128-139
• 41 Nieman DC. Upper respiratory tract infections and exercise.  Thorax. 1995;  50 1229-1231
• 42 Nystad W, Harris J R, Borgen S J. Asthma and wheezing among Norwegian elite athletes.  Med Sci Sports Exerc. 2000;  32 266-270
• 43 Nystad W. The physical activity level of children with asthma.  Scand J Med Sci Sports. 1997;  7 331-335
• 44 Nystad W, Magnus P, Røksund O, Svidal B, Hetlevik Ø. The prevalence of respiratory symptoms and asthma among school children in three different areas of Norway.  Pediatr Allergy Immunol. 1997;  8 35-40
• 45 Omran M, Russel G. Continuing increase in respiratory symptoms and atopy in Aberdeen schoolchildren.  BMJ. 1996;  312 34
• 46 Peat J K, van den Berg R H, Green W F, Mellis C M, Leeder S R, Woolcock A J. Changing prevalence of asthma in Australian children.  BMJ. 1994;  308 1591-1596
• 47 Pearce N, Pekkanen J, Beasley R. How much asthma is really attribuable to atopy?.  Thorax. 1999;  54 268-272
• 48 Platts-Mills T A. How environment affects patients with disease: indoor allergens and asthma.  Ann Allergy. 1994;  72 381-384
• 49 Platts-Mills T A, Ward G W. Epidemiology of the relationship between exposure to indoor allergen and asthma.  Int Arch Allergy Appl Immunol. 1991;  94 339-345
• 50 Redline S, Gold D. Challenges in interpreting gender differences in asthma.  Am J Respir Crit Care Med. 1994;  150 1219-1221
• 51 Rice S G, Bierman C W, Shapiro G G, Furukawa C T, Pierson W E. Identification of exercise-induced asthma among intercollegiate athletes.  Ann Allergy. 1985;  55 790-793
• 52 Rimpelæ A H, Savonius B, Rimpelæ M K, Haahtela T. Asthma and allergic rhinitis among Finnish adolescents in 1977 - 1991.  Scand J Soc Med. 1995;  23 60-65
• 53 Santuz P, Baraldi E, Filippone M, Zachello F. Exercise performance in children with asthma: is it different from that of healthy controls?.  Eur Respir J. 1997;  10 1254-1260
• 54 Shaw R A, Crane J, Pearce N E. Validation of a video questionnaire for assessing asthma prevalence.  Clin Exp Allergy. 1992;  22 562-569
• 55 Shaw R A, Crane J, O'Donell T V, Porteus L E, Coleman E D. Increasing asthma prevalence in a rural New Zealand adolescent population: 1975 - 1989.  Arch Dis Child. 1990;  65 1319-1323
• 56 Shaw R, Woodman K, Ayson M, Dibdin S, Winkelman R, Crane J, Beasley R, Pearce N. Measuring the prevalence of bronchial hyper-responsiveness in children.  Int J Epidemiol. 1995;  24 597-602
• 57 Sheffer A L, Bousquet J, Busse W W, Clark T, Dahl R, Evans D, Fabbri L M, Hargreave F E, Holgate S T. International consesus report on diagnosis and treatment of asthma.  Eur Respir J. 1992;  5 601-641
• 58 Sherman C B, Tosteson T D, Tager I B. Early childhood predictors of asthma.  Am J Epidemiol. 1990;  132 83-95
• 59 Sherman C B, Tosteson T D, Tager I B, Speizer F E, Weiss S T. Early childhood predictors of asthma.  Am J Epidemiol. 1990;  132 83-95
• 60 Sibbald B, Horn M, Gregg I. A family study of the genetic basis of asthma and wheezy bronchitis.  Arch Dis Child. 1980;  55 354-357
• 61 Skadhauge L, Christensen K, Kyvik K, Sigsgaard T. Genetic and environmental influence on asthma: a population-based study of 11 688 Danish twin pairs.  Eur Respir J. 1999;  13 8-14
• 62 Strachan D P. Hay fever, hygiene and household size.  BMJ. 1989;  299 1259-1260
• 63 Strachan D P, Anderson H R, Limbs E S, O'Neill A, Wells N. A national survey of asthma prevalence, severity, and treatment in Great Britain.  Arch Dis Child. 1994;  70 174-178
• 64 Sue-Chu M, Karjalainen A, Altraja A, Laitinen L, Naess A, Larsson L, Bjermer L. Lymphoid aggregates in endobronchial biopsis from young elite cross-country skiers.  Am J Respir Crit Care Med. 1998;  158 597-601
• 65 Sue-Chu M, Larsson L, Moen T, Rennard S I, Bjermer L. Bronchoscopy and bronchoalveolar lavage findings in cross-country skiers with and without “ski asthma”.  Eur Respir J. 1999;  13 626-632
• 66 Taylor W R, Newacheck P W. Impact of childhood asthma on health.  Pediatrics. 1992;  90 657-662
• 67 Tepper R, Morgan W, Cota K, Wright A, Taussig L. Physiologic growth and development of the lung during the first years of life.  Am Rev Respir Dis. 1986;  134 513-519
• 68 The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee . Worldwide variations in the prevalence of asthma symptoms: The International Study of Asthma and Allergies in Childhood (ISAAC).  Eur Respir J. 1998;  12 315-340
• 69 The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee . Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema: ISAAC.  Lancet. 1998;  351 1225-1232
• 70 Vall O, Sancho N, Sunyer J, Anto J M, Busquets R M. Prevalence of asthma-related symptoms and bronchial responsiveness to exercise in children 13 - 14 years in Barcelona, Spain.  Eur Respir J. 1996;  9 2094-2098
• 71 von Mutius E, Martinez F D, Fritzsch C, Nicolai T, Roell G, Thieman H H. Prevalence of asthma and atopy in two areas of West and East Germany.  Am J Respir Crit Care Med. 1994;  149 358-364
• 72 Voy R O. The US Olympic Committee experience with exercise-induced bronchospasm, 1984.  Med Sci Sports Exerc. 1986;  18 328-330
• 73 Wardlaw A J. The role of air pollution in asthma.  Clin Exp Allergy. 1993;  23 81-96
• 74 Weiler J M, Metzger W J, Donnelly A L, Crowley E T, Sharat M D. Prevalence of bronchial hyperresponsiveness in highly trained athletes.  Chest. 1986;  90 23-28
• 75 Wilson N, Silverman M. Bronchial responsiveness and its measurement. In: Silverman M (ed) Childhood asthma and other wheezing disorders. London; Chapman & Hall 1995: 141-174